How do you divide (-x^4+6x^3+8x+12)/(x^2-3x+9)x4+6x3+8x+12x23x+9?

1 Answer
May 17, 2016

Dividing -x^4+6x^3+8x+12x4+6x3+8x+12 by x^2-3x+9x23x+9,

the quotient is -x^2+3x+18x2+3x+18 and remainder is 35x-15035x150

Explanation:

To divide -x^4+6x^3+8x+12x4+6x3+8x+12 by x^2-3x+9x23x+9,

as -x^4/x^2=-x^2x4x2=x2.

Now -x^2xx(x^2-3x+9)=-x^4+3x^3-9x^2x2×(x23x+9)=x4+3x39x2

Subtracting -x^4+3x^3-9x^2x4+3x39x2 from -x^4+6x^3+8x+12x4+6x3+8x+12, we get

(-x^4+6x^3+8x+12)-(-x^4+3x^3-9x^2)=3x^3+9x^2+8x+12(x4+6x3+8x+12)(x4+3x39x2)=3x3+9x2+8x+12

Now in similar way 3x^3+9x^2+8x+123x3+9x2+8x+12, x^2-3x+9x23x+9 can go 3x3x times and remainder will be

3x^3+9x^2+8x+12-3x(x^2-3x+9)3x3+9x2+8x+123x(x23x+9)

= 3x^3+9x^2+8x+12-3x^3+9x^2-27x3x3+9x2+8x+123x3+9x227x

= 18x^2-19x+1218x219x+12

Now in this, x^2-3x+9x23x+9 goes 1818 times and remainder is

18x^2-19x+12-18(x^2-3x+9)=-19x+54x+12-162=35x-15018x219x+1218(x23x+9)=19x+54x+12162=35x150

Hence when we divide -x^4+6x^3+8x+12x4+6x3+8x+12 by x^2-3x+9x23x+9, the quotient is -x^2+3x+18x2+3x+18 and remainder is 35x-15035x150